Question

-20+{[7+5+(-9+7)+3]} pfvr faça a conta

Answer 1

-20+{[7+5-2+3]}
-20+{13}
-20+13
-7
espero ter ajudado..

Answer 2

-20+{[7+5+(-9+7)+3]}=
-20+{[7+5+(-2)+3]}=
-20+{[7+5+1]}=
-20+{[7+6]}=
-20+13+
-7